An Efficacy and Safety Study w/ Azstarys® in Children 4-12 Years of Age With ADHD

Inclusion Criteria

• In Cohort 1, subjects must be at least 4 years old and less than 5 years and 10 months at Screening; in Cohort 2, subjects must be at least 6 years old and less than 12 years and 10 months at Screening.
• Subjects must have a body weight within the 5th and 95th percentile according to the gender-specific weight-for-age percentile charts from the Centers for Disease Control and Prevention (CDC). See calculator at https://www.infantchart.com/child/.
• Female subjects must agree, if they are of childbearing potential at Screening or when they become of childbearing potential during the study, to remain abstinent or agree to use an effective and medically acceptable form of birth control from the time of written or verbal assent to at least 14 days after the last dose of study drug. Childbearing potential is defined as follows: Girls under the age of 12 who have not had their first period will be considered "not of child-bearing potential." Girls 12 years of age (including girls who will become 13 years during the study) will be considered "of child-bearing potential," even if they have not yet had their first period. Irrespective of age, girls who have had their first period, will be considered "of child-bearing potential."
• Subjects must be in general good health defined as the absence of any clinically relevant abnormalities as determined by the Investigator based on physical examinations, vital signs, electrocardiograms (ECGs), medical history, and clinical laboratory values (chemistry, hematology, urinalysis) at Screening. If any of the chemistry or hematology tests are not within the laboratory's reference range, then the subject can be included only if the Investigator determines the deviations to be not clinically relevant.
• At least one parent/legal guardian of the subject must voluntarily give written permission for him/her to participate in the study.
• Subjects in Cohort 2 must give written or verbal assent prior to study participation. For verbal assent, the procedure will be documented and signed by a witness. A parent or guardian may not be the witness for a child's verbal assent document.
• Subject must meet Diagnostic and Statistical Manual of Mental Disorders - Fifth Edition (DSM-5) criteria for a primary diagnosis of ADHD (combined, inattentive, or hyperactive/impulsive presentation) per clinical evaluation and confirmed by Mini-International Neuropsychiatric Interview for Children and Adolescents (MINI Kid).
• Subject has had ADHD symptoms present for at least 6 months prior to the Screening Visit.
• Subject must be able and willing to wash out current stimulant ADHD medications, including herbal medications, from 5 days prior to the start of the Treatment Period, and abstain from taking these to the end of Visit 6 or ET; and wash out non-stimulant ADHD medications from 14 days prior to the start of the Treatment Period, and abstain from taking these to the end of Visit 6.
• Subject must have a score of ≥4 (Moderately Ill) on the clinician-administered Clinical Global Impressions-Severity (CGI-S) scale. For subjects requiring washout of ADHD medications, this criterion refers to a score following washout.
• Subjects must have age and sex adjusted ratings of ≥90th percentile Total Score on the ADHD-Rating Scale (ADHD-RS) rated over the past 6 months (for 4- and 5-year old children, use Preschool Version of ADHD-RS-IV; for 6-12 years old children, use ADHD-RS-5).
• Subject functions at an age-appropriate level intellectually, as determined by the Investigator.
• Subject must have a systolic and diastolic blood pressure below the 95th percentile for age and gender according to the 2017 AAP guidelines (Flynn 2017) based on the average of 3 measurements 2-5 minutes apart.
• Subject, subject's parent/legal guardian, and caregiver (if applicable) must understand and be willing and able to comply with all study procedures and visit schedule.
• Subject, parent/legal guardian